Multifocal spectacle lens with high positive focal power

Claim 2

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by the near segment (N) being aspheric in form and separated from the focal section above it (F or Z) by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian carrying over from the near segment into the focal section (1) by transecting the horizontal dividing line, the dividing line disapperaing mathematically at the main meridian, to provide thereby a transition along the main meridian between the near portion and the focal section, said transition being continuous to substantially avoid any jump in transition of vision along the meridian from the focal section to the near segment, or from the near segment to the focal section, along the main meridian.

Claim 3

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance portion by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over from the near segment into and across the intermediate portion into the distance portion transecting the horizontal dividing lines, the dividing lines disappearing mathematically at the main meridian, to provide thereby a transistion along the main meridian between the near portion and the intermediate portion and between the intermediate portion and the distance portion, said transitions being continuous to substantially avoid any jump, in transition of vision along the main meridian from one section to the next.

Claim 4

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance portion by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over from the near segment into and across the intermediate portion into the distance portion transecting the horizontal dividing lines, the dividing lines disappearing mathematically at the main meridian, to provide thereby a transistion along the main meridian between the near portion and the intermediate portion and between the intermediate portion and the distance portion, said transitions being continuous to substantially avoid any jump, in transition of vision along the main meridian from one section to the next.

Claim 5

A spectacle lens according to claims 1 or 2, characterized by the fact that the tangents in the direction of the main meridian (7) at the transition points on the main meridian between the individual sections of the focal portion include an angle of approximately 0.5°.

Claim 6

A spectacle lens according to any one of claims 1 or 2, characterized by the fact that the optical center of the distance portion is situated roughly 1 mm above the dividing line to the portion below.

Claim 7

A spectacle lens according to claim 4, characterized by the fact that the height of the intermediate portion is approximately 10 mm.

Claim 8

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance provided by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, the optical center of the distance portion being situated roughly 1 mm above the dividing line to the portion below, the height of the intermediate portion being approximately 10 mm, the transition zone surrounding the focal portion being designed in such a way the dividing line between the individual sections of the focal portion disappear in the transition zone and the rim zones of all sections are uniform, and wherein the transition zone corresponds to the general equation ##EQU4## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z or N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion (1) and the rim zone (3), which forms an afocal margin of constant thickness with the inside surface.

Claim 9

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance provided by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, the optical center of the distance portion being situated roughly 1 mm above the dividing line to the portion below, the height of the intermediate portion being approximately 10 mm, the transition zone surrounding the focal portion being designed in such a way the dividing line between the individual sections of the focal portion disappear in the transition zone and the rim zones of all sections are uniform, and wherein the transition zone corresponds to the general equation ##EQU4## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z or N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion (1) and the rim zone (3), which forms an afocal margin of constant thickness with the inside surface.

Claim 10

A spectacle lens according to claim 6, characterized by the fact that the intermediate portion is optimized for a distance of approximately 0.5 to 0.7 m and the near segment for a distance of approximately 0.3 to 0.5 m.

Claim 11

A spectacle lens according to claim 7, characterized by the fact that each of the sections of the focal portion is a surface segment from a rotationally symmetrical surface corresponding to the general formula ##EQU5## where, z=the distance (sagitta) of a point on the surface from the vertex of the surface, h=the distance of this point from the optical axis, and C is determined by the desired focal power of each individual section of the focal portion, and by the fact that the aspheric coefficients K, I 3 , I 4 , I 5 and I 6 are determined in such a way that the visual acuity in the whole area of the angle of view through the individual portion is maximal.

Claim 12

A spectacle lens according to claim 7, characterized by the fact that the near segment and, where present, the intermediate portion are designed torically or atorically in such a way that the oblique astigmatism is compensated for.

Claim 13

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section with an additional near segment, a transition zone surrounding the focal section and a rim zone, and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion situated between the near segment and the distance portion, the transition zone being separated from the distance portion by a substantially horizontal dividing line having an approximately straight course, the near segment being aspheric in form and separated from the intermediate portion above it by a substantially horizontal dividing line which has an approximately straight course, the lens having a main vertical meridian passing through an optical axis of the lens, the main meridian within the near segment carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion, continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, each of the sections of the focal portion being a surface segment from a rotationally symmetrical surface corresponding to the general formula ##EQU6## where z=the distance (sagitta) of a point on the surface from the vertex of this surface, h=the distance of this point from the optical axis, and C is determined by the desired focal power of each individual section of the focal portion, and by the fact that the aspheric coefficients K, I 3 , I 4 , I 5 and I 6 are determined in such a way that the visual acuity in the whole area of the angle of view through the individual portion is maximal, the transition zone (2) corresponding to the general equation ##EQU7## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z,N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion and the rim zone which forms an afocal margin of constant thickness with the inside surface.

Claim 14

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section with an additional near segment, a transition zone surrounding the focal section and a rim zone, and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion situated between the near segment and the distance portion, the transition zone being separated from the distance portion by a substantially horizontal dividing line having an approximately straight course, the near segment being aspheric in form and separated from the intermediate portion above it by a substantially horizontal dividing line which has an approximately straight course, the lens having a main vertical meridian passing through an optical axis of the lens, the main meridian within the near segment carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion, continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, each of the sections of the focal portion being a surface segment from a rotationally symmetrical surface corresponding to the general formula ##EQU6## where z=the distance (sagitta) of a point on the surface from the vertex of this surface, h=the distance of this point from the optical axis, and C is determined by the desired focal power of each individual section of the focal portion, and by the fact that the aspheric coefficients K, I 3 , I 4 , I 5 and I 6 are determined in such a way that the visual acuity in the whole area of the angle of view through the individual portion is maximal, the transition zone (2) corresponding to the general equation ##EQU7## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z,N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion and the rim zone which forms an afocal margin of constant thickness with the inside surface.

Claim 15

A spectacle lens according to claim 10 characterized by the fact that the tangents in the direction of the main meridian at the transition points on the main meridian between the individual sections of the focal portion include an angle of approximately 0.5°.

Claim 16

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance portion by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, the transition zone surrounding the focal portion being designed in such a way the dividing line between the individual sections of the focal portion disappears mathematically in the transition zone and the rim zones of all sections are uniform, and wherein the transition zone corresponds to the general equation ##EQU8## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z or N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion (1) and the rim zone (3), which forms an afocal margin of constant thickness with the inside surface.

Claim 17

A multifocal spectacle lens with a high positive focal power, with a convex front surface, which comprises an aspheric focal section (1) having a distance portion (F) with an additional near segment (N), a transition zone (2) surrounding the focal section and a rim zone (3), and including an inside surface which forms an afocal margin together with the rim zone, characterized by there being an aspheric intermediate portion (Z) situated between the near segment (N) and the distance portion (F), the intermediate portion being separated from the distance portion by a substantially horizontal dividing line (5) having an approximately straight course, the near segment (N) being aspheric in form and separated from the transition zone (Z) above it by a substantially horizontal dividing line (6) which has an approximately straight course, the lens having a main vertical meridian (7) passing through an optical axis (9) of the lens, the main meridian within the near segment (N) carrying over into the intermediate portion continuously and practically without any jump, and the main meridian within the intermediate portion carrying over into the distance portion continuously and practically without any jump, such that the lens is substantially jumpless along the main meridian from one section to the next, the transition zone surrounding the focal portion being designed in such a way the dividing line between the individual sections of the focal portion disappears mathematically in the transition zone and the rim zones of all sections are uniform, and wherein the transition zone corresponds to the general equation ##EQU8## where z=the distance of a point from the vertex of the front surface in the direction of the optical axis, and h=the distance of this point from the optical axis, and by the fact that the coefficients a i ,F,Z or N are determined in such a way that with regard to the functional value and the first derivative the transition zone is always situated at the respective part (F,Z,N) of the focal portion (1) and the rim zone (3), which forms an afocal margin of constant thickness with the inside surface.